#pragma GCC optimize(2, "Ofast", "inline")
#include <iostream>
#include <vector>
#include <map>
#include <cmath>
#include <set>
#include <queue>
#include <stack>
#include <list>
#include <unordered_map>
#include <algorithm>
#define endl '\n'
#define int long long
#define pii pair<int, int>
using namespace std;

// 已知
int n, s, pre, ti;
// 未知

signed main()
{
    cin.tie(0)->sync_with_stdio(0);
    cin >> n >> s;
    cin >> pre;
    for (int i = 0;i < n - 1;++i)
    {
        cin >> ti;
        if (ti - pre > s + 0.5)
        {
            cout << "No" << endl;
            return 0;
        }
        pre = ti;
    }
    cout << "Yes" << endl;

    return 0;
}